The present invention relates to a new and distinct cultivar of poinsettia plant known by the cultivar name xe2x80x98Fisson Dark Redxe2x80x99 and botanically known as Euphorbia pulcherrima. 
xe2x80x98Fisson Dark Redxe2x80x99 is a product of a mutation induction program carried out by the inventor, Katharina Zerr, in Hillscheid, Germany, in 1994. The primary objective of the induction program was to expand the bract color ranges of xe2x80x98Fissonxe2x80x99 (U.S. Plant Pat. No. 9,365). xe2x80x98Fissonxe2x80x99 is characterized by its intense red-colored bracts with strong, pointed lobes, dark-green foliage and relatively compact and bushy habit.
The irradiation program comprised exposing rooted cuttings taken from plants of the parent cultivar to an X-ray source of 30 Gy dosage in Ahrensburg, Germany, under the supervision of the inventor. The irradiated plants were grown out in a greenhouse in Hillscheid, Germany, and were asexually propagated by the inventor by taking cuttings. The plants resulting from these cuttings were screened for mutations as small, flowering, single-stem plants beginning in autumn of 1994 and continuing thereafter. The mutations discovered were identified by numbers. Parts of plants exhibiting a mutation of interest were left to develop vegetative shoots which were used as cuttings and grown out.
xe2x80x98Fisson Dark Redxe2x80x99 originated from a single plant (no. 558) displaying distinctly darker red and differently shaped bracts, that was discovered in the late summer of 1995. The apparently completely mutated plant was propagated vegetatively by taking cuttings, and the resulting plants were examined for uniformity in the spring of 1996 prior to further propagation. The clone was examined more closely and compared to the original variety xe2x80x98Fissonxe2x80x99 and to other cultivars in autumn of 1997. Horticultural examination of the clone starting in 1997 and continuing thereafter has confirmed that the combination of characteristics as herein disclosed for xe2x80x98Fisson Dark Redxe2x80x99 are firmly fixed and retained through successive generations of asexual reproduction.
The following traits have been repeatedly observed and are determined to be basic characteristics of xe2x80x98Fisson Dark Redxe2x80x99, which in combination distinguish this Poinsettia as a new and distinct cultivar:
1. uniform dark-red bract color;
2. medium-sized, star-shaped inflorescence with narrow, slightly lobed bracts;
3. intense dark-green foliage with weak dentation;
4. compact and well-branched, round plant habit; and
5. medium to late flowering.
xe2x80x98Fisson Dark Redxe2x80x99 has not been observed under all possible environmental conditions. The phenotype may vary significantly with variations in environment such as temperature, light intensity, and daylength without any change in the genotype. The following observations, measurements and comparisons describe plants grown in Langley, British Columbia, Canada, under greenhouse conditons which approximate those generally used in commercial practice.
Of the many commercial cultivars known to the inventor, the most similar in comparison to xe2x80x98Fisson Dark Redxe2x80x99 are the parent cultivar xe2x80x98Fissonxe2x80x99 and the co-pending variety xe2x80x98Fisson Dark Redxe2x80x99 (U.S. Plant patent application Ser. No. 09/496,196). In comparison to xe2x80x98Fissonxe2x80x99, xe2x80x98Fisson Dark Redxe2x80x99 has a darker-red bract color, narrower bracts and leaves and a more intense anthocyanin coloration of petioles and stems, and a somewhat more compact plant habit. Plants of xe2x80x98Fisson Dark Redxe2x80x99 were approximately 5 cm shorter and 5-10 cm narrower than plants of xe2x80x98Fissonxe2x80x99. xe2x80x98Fisson Dark Redxe2x80x99 may take about 7-10 days longer to become marketable, due to the smaller bracts of xe2x80x98Fisson Dark Redxe2x80x99, while the development of the cyathia is almost similar to those of xe2x80x98Fissonxe2x80x99.
In comparison to xe2x80x98Fiscor Dark Redxe2x80x99, xe2x80x98Fisson Dark Redxe2x80x99 has a somewhat more brillant hue of bract color, narrower bracts and leaves with more distinct lobes, and a narrower plant habit.